Publications by Subir Sarkar

Simplified Models for Dark Matter Searches at the LHC


J Abdallah, E others, R Lucas, M Thomas, I Tomalin, M Wielers, S Worm, B Feldstein, U Haisch, A Hibbs, E Re, S Sarkar

This document outlines a set of simplified models for dark matter and its interactions with Standard Model particles. It is intended to summarize the main characteristics that these simplified models have when applied to dark matter searches at the LHC, and to provide a number of useful expressions for reference. The list of models includes both s-channel and t-channel scenarios. For s-channel, spin-0 and spin-1 mediation is discussed, and also realizations where the Higgs particle provides a portal between the dark and visible sectors. The guiding principles underpinning the proposed simplified models are spelled out, and some suggestions for implementation are presented.

Multipole analysis of IceCube data to search for dark matter accumulated in the Galactic halo: IceCube Collaboration

European Physical Journal C (2015)

M Ackermann, J Adams, JA Aguilar, M Ahlers, M Ahrens, D Altmann, T Anderson, C Arguelles, TC Arlen, J Auffenberg, X Bai, SW Barwick, V Baum, JJ Beatty, J Becker Tjus, KH Becker, S BenZvi, P Berghaus, D Berley, E Bernardini, A Bernhard, DZ Besson, G Binder, D Bindig

© 2015, The Author(s). Dark matter which is bound in the Galactic halo might self-annihilate and produce a flux of stable final state particles, e.g. high energy neutrinos. These neutrinos can be detected with IceCube, a cubic-kilometer sized Cherenkov detector. Given IceCube’s large field of view, a characteristic anisotropy of the additional neutrino flux is expected. In this paper we describe a multipole method to search for such a large-scale anisotropy in IceCube data. This method uses the expansion coefficients of a multipole expansion of neutrino arrival directions and incorporates signal-specific weights for each expansion coefficient. We apply the technique to a high-purity muon neutrino sample from the Northern Hemisphere. The final result is compatible with the null-hypothesis. As no signal was observed, we present limits on the self-annihilation cross-section averaged over the relative velocity distribution (Formula Presented.) down to ([Formula Presented.) for a dark matter particle mass of 700–1,000 GeV and direct annihilation into (Formula Presented.). The resulting exclusion limits come close to exclusion limits from γ-ray experiments, that focus on the outer Galactic halo, for high dark matter masses of a few TeV and hard annihilation channels.

Full-sky analysis of cosmic-ray anisotropy with IceCube and HAWC

Proceedings of Science 30-July-2015 (2015)

JC Díaz-Vélez, D Fiorino, P Desiati, S Westerhoff, E De La Fuente

During the past two decades, experiments in both the Northern and Southern hemispheres have observed a small but measurable energy-dependent sidereal anisotropy in the arrival direction distribution of galactic cosmic rays. The relative amplitude of the anisotropy is 10-4 -10-3. However, each of these individual measurements is restricted by limited sky coverage, and so the pseudo-power spectrum of the anisotropy obtained from any one measurement displays a systematic correlation between different multipole modes C. To address this issue, we present the preliminary status of a joint analysis of the anisotropy on all angular scales using cosmic-ray data from the IceCube Neutrino Observatory located at the South Pole (90 S) and the High-Altitude Water Cherenkov (HAWC) Observatory located at Sierra Negra, Mexico (19 N). We describe the methods used to combine the IceCube and HAWC data, address the individual detector systematics and study the region of overlapping field of view between the two observatories.

IceCube-Gen2: A Vision for the Future of Neutrino Astronomy in Antarctica


S Sarkar

The recent observation by the IceCube neutrino observatory of an astrophysical flux of neutrinos represents the “first light” in the nascent field of neutrino astronomy. The observed diffuse neutrino flux seems to suggest a much larger level of hadronic activity in the non-thermal universe than previously thought and suggests a rich discovery potential for a larger neutrino observatory. This document presents a vision for an substantial expansion of the current IceCube detector, IceCubeGen2 , including the aim of instrumenting a 10 km3 volume of clear glacial ice at the South Pole to deliver substantial increases in the astrophysical neutrino sample for all flavors. A detector of this size would have a rich physics program with the goal to resolve the sources of these astrophysical neutrinos, discover GZK neutrinos, and be a leading observatory in future multi-messenger astronomy programs.

A hadronic explanation of the lepton anomaly

Journal of Physics: Conference Series IOP Publishing 531 (2014) 012008-012008

P Mertsch, S Sarkar

The rise in the positron fraction, observed by PAMELA, Fermi-LAT and most recently by AMS-02, has created a lot of interest, fuelled by speculations about an origin in dark matter annihilation in the Galactic halo. However, other channels, e.g. antiprotons or gamma-rays, now severely constrain dark matter interpretations, thus requiring astrophysical sources of positrons. We have investigated the possibility that supernova remnants, the most likely sources of Galactic cosmic rays, can in fact also produce a hard spectrum of secondary positrons, by spallation and acceleration at the shock. This mechanism is guaranteed if hadronic CRs are present and would also lead to observable signatures in other secondary channels like the boron-to-carbon or antiproton-to-proton ratios. If such features were borne out by upcoming AMS-02 data, this would rule out other explanations.

Erratum: IceCube sensitivity for low-energy neutrinos from nearby supernovae(Astronomy and Astrophysics (2011) 535 : A109 (DOI: 10.1051/0004-6361/201117810))

Astronomy and Astrophysics 563 (2014)

R Abbasi, Y Abdou, T Abu-Zayyad, M Ackermann, J Adams, JA Aguilar, M Ahlers, MM Allen, D Altmann, K Andeen, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JL Bazo Alba, K Beattie, JJ Beatty, S Bechet, JK Becker, KH Becker, ML Benabderrahmane, S BenZvi, J Berdermann, P Berghaus, D Berley, E Bernardini, D Bertrand, DZ Besson, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, C Bohm, D Bose, S Böser, O Botner, AM Brown, S Buitink, KS Caballero-Mora, M Carson, D Chirkin, B Christy, F Clevermann, S Cohen, C Colnard, DF Cowen, AH Cruz Silva, MV D'Agostino, M Danninger, J Daughhetee, JC Davis, C De Clercq, T Degner, L Demirörs, F Descamps, P Desiati, G De Vries-Uiterweerd, T Deyoung, JC Díaz-Vélez, M Dierckxsens, J Dreyer, JP Dumm, M Dunkman, J Eisch, RW Ellsworth, O Engdegård, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, BD Fox, A Franckowiak, R Franke, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, JA Goodman, D Góra, D Grant, T Griesel, A Groß, S Grullon, M Gurtner, C Ha, A Hajismail, A Hallgren, F Halzen, K Han

Big-Bang Nucleosynthesis

Review of Partical Physics. Chinese Physics C 38 (2014) 090001-

S Sarkar, BD Fields, P Molaro

A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, $\eta$, corresponding to the inferred primordial abundances of deuterium and helium-4 is consistent with the independent determination of $\eta$ from observations of anisotropies in the cosmic microwave background. However the primordial abundance of lithium-7 inferred from observations is significantly below its expected value. Taking systematic uncertainties in the abundance estimates into account, there is overall concordance in the range $\eta = (5.7-6.7)\times 10^{-10}$ at 95% CL (corresponding to a cosmological baryon density $\Omega_B h^2 = 0.021 - 0.025$). The D and He-4 abundances, when combined with the CMB determination of $\eta$, provide the bound $N_\nu=3.28 \pm 0.28$ on the effective number of neutrino species. Other constraints on new physics are discussed briefly.

Observation of high-energy astrophysical neutrinos in three years of IceCube data

Physical Review Letters American Physical Society 113 (2014) 101101-101101

Aartsen, S Sarkar

A search for high-energy neutrinos interacting within the IceCube detector between 2010 and 2012 provided the first evidence for a high-energy neutrino flux of extraterrestrial origin. Results from an analysis using the same methods with a third year (2012-2013) of data from the complete IceCube detector are consistent with the previously reported astrophysical flux in the 100 TeV-PeV range at the level of 10(-8)  GeV cm-2 s-1 sr-1 per flavor and reject a purely atmospheric explanation for the combined three-year data at 5.7σ. The data are consistent with expectations for equal fluxes of all three neutrino flavors and with isotropic arrival directions, suggesting either numerous or spatially extended sources. The three-year data set, with a live time of 988 days, contains a total of 37 neutrino candidate events with deposited energies ranging from 30 to 2000 TeV. The 2000-TeV event is the highest-energy neutrino interaction ever observed.

Search for non-relativistic Magnetic Monopoles with IceCube

European Physical Journal C Springer Verlag C74 (2014) 2938-2938

S Sarkar

The IceCube Neutrino Observatory is a large Cherenkov detector instrumenting $1\,\mathrm{km}^3$ of Antarctic ice. The detector can be used to search for signatures of particle physics beyond the Standard Model. Here, we describe the search for non-relativistic, magnetic monopoles as remnants of the GUT (Grand Unified Theory) era shortly after the Big Bang. These monopoles may catalyze the decay of nucleons via the Rubakov-Callan effect with a cross section suggested to be in the range of $10^{-27}\,\mathrm{cm^2}$ to $10^{-21}\,\mathrm{cm^2}$. In IceCube, the Cherenkov light from nucleon decays along the monopole trajectory would produce a characteristic hit pattern. This paper presents the results of an analysis of first data taken from May 2011 until May 2012 with a dedicated slow-particle trigger for DeepCore, a subdetector of IceCube. A second analysis provides better sensitivity for the brightest non-relativistic monopoles using data taken from May 2009 until May 2010. In both analyses no monopole signal was observed. For catalysis cross sections of $10^{-22}\,(10^{-24})\,\mathrm{cm^2}$ the flux of non-relativistic GUT monopoles is constrained up to a level of $\Phi_{90} \le 10^{-18}\,(10^{-17})\,\mathrm{cm^{-2}s^{-1}sr^{-1}}$ at a 90% confidence level, which is three orders of magnitude below the Parker bound. The limits assume a dominant decay of the proton into a positron and a neutral pion. These results improve the current best experimental limits by one to two orders of magnitude, for a wide range of assumed speeds and catalysis cross sections.

Fingerprints of Galactic Loop I on the Cosmic Microwave Background

Astrophys.J. 789 (2014) L29-L29

H Liu, P Mertsch, S Sarkar



A Aab, P Abreu, M Aglietta, M Ahlers, EJ Ahn, I Al Samarai, IFM Albuquerque, I Allekotte, J Allen, P Allison, A Almela, JA Castillo, J Alvarez-Muniz, RA Batista, M Ambrosio, A Aminaei, L Anchordoqui, S Andringa, C Aramo, F Arqueros, H Asorey, P Assis, J Aublin, M Ave, M Avenier, G Avila, AM Badescu, KB Barber, J Baeuml, C Baus, JJ Beatty, KH Becker, JA Bellido, C Berat, X Bertou, PL Biermann, P Billoir, F Blanco, M Blanco, C Bleve, H Bluemer, M Bohacova, D Boncioli, C Bonifazi, R Bonino, N Borodai, J Brack, I Brancus, P Brogueira, WC Brown, P Buchholz, A Bueno, M Buscemi, KS Caballero-Mora, B Caccianiga, L Caccianiga, M Candusso, L Caramete, R Caruso, A Castellina, G Cataldi, L Cazon, R Cester, AG Chavez, SH Cheng, A Chiavassa, JA Chinellato, J Chudoba, M Cilmo, RW Clay, G Cocciolo, R Colalillo, L Collica, MR Coluccia, R Conceicao, F Contreras, MJ Cooper, S Coutu, CE Covault, A Criss, J Cronin, A Curutiu, R Dallier, B Daniel, S Dasso, K Daumiller, BR Dawson, RM de Almeida, M De Domenico, SJ de Jong, JRTDM Neto, I De Mitri, J de Oliveira, V de Souza, L del Peral, O Deligny, H Dembinski, N Dhital, C Di Giulio, A Di Matteo, JC Diaz, MLD Castro, PN Diep, F Diogo, C Dobrigkeit, W Docters, JC D'Olivo, PN Dong, A Dorofeev, QD Hasankiadeh, MT Dova, J Ebr, R Engel, M Erdmann, M Erfani, CO Escobar, J Espadanal, A Etchegoyen, PFS Luis, H Falcke, K Fang, G Farrar, AC Fauth, N Fazzini, AP Ferguson, M Fernandes, B Fick, JM Figueira, A Filevich, A Filipcic, BD Fox, O Fratu, U Froehlich, B Fuchs, T Fuji, R Gaior, B Garcia, ST Garcia Roca, D Garcia-Gamez, D Garcia-Pinto, G Garilli, AG Bravo, F Gate, H Gemmeke, PL Ghia, U Giaccari, M Giammarchi, M Giller, C Glaser, H Glass, FG Albarracin, M Gomez Berisso, PF Gomez Vitale, P Goncalves, JG Gonzalez, B Gookin, A Gorgi, P Gorham, P Gouffon, S Grebe, N Griffith, AF Grillo, TD Grubb, Y Guardincerri, F Guarino, GP Guedes, P Hansen, D Harari, TA Harrison, JL Harton, A Haungs, T Hebbeker, D Heck, P Heimann, AE Herve, GC Hill, C Hojvat, N Hollon, E Holt, P Homola, JR Hoerandel, P Horvath, M Hrabovsky, D Huber, T Huege, A Insolia, PG Isar, K Islo, I Jandt, S Jansen, C Jarne, M Josebachuili, A Kaeaepae, O Kambeitz, KH Kampert, P Kasper, I Katkov, B Kegl, B Keilhauer, A Keivani, E Kemp, RM Kieckhafer, HO Klages, M Kleifges, J Kleinfeller, R Krause, N Krohm, O Kroemer, D Kruppke-Hansen, D Kuempel, N Kunka, G La Rosa, D LaHurd, L Latronico, R Lauer, M Lauscher, P Lautridou, S Le Coz, MSAB Leao, D Lebrun, P Lebrun, MAL de Oliveira, A Letessier-Selvon, I Lhenry-Yvon, K Link, R Lopez, AL Aguera, K Louedec, JL Bahilo, L Lu, A Lucero, M Ludwig, H Lyberis, MC Maccarone, M Malacari, S Maldera, J Maller, D Mandat, P Mantsch, AG Mariazzi, V Marin, IC Maris, G Marsella, D Martello, L Martin, H Martinez, OM Bravo, D Martraire, JJM Meza, HJ Mathes, S Mathys, AJ Matthews, J Matthews, G Matthiae, D Maurel, D Maurizio, E Mayotte, PO Mazur, C Medina, G Medina-Tanco, M Melissas, D Melo, E Menichetti, A Menshikov, S Messina, R Meyhandan, S Micanovic, MI Micheletti, L Middendorf, IA Minaya, L Miramonti, B Mitrica, L Molina-Bueno, S Mollerach, M Monasor, DM Ragaigne, F Montanet, C Morello, JC Moreno, M Mostafa, CA Moura, MA Muller, G Mueller, M Muenchmeyer, R Mussa, G Navarra, S Navas, P Necesal, L Nellen, A Nelles, J Neuser, M Niechciol, L Niemietz, T Niggemann, D Nitz, D Nosek, V Novotny, L Nozka, L Ochilo, A Olinto, M Oliveira, M Ortiz, N Pacheco, DP Selmi-Dei, M Palatka, J Pallotta, N Palmieri, P Papenbreer, G Parente, A Parra, S Pastor, T Paul, M Pech, J Pekala, R Pelayo, IM Pepe, L Perrone, R Pesce, E Petermann, C Peters, S Petrera, A Petrolini, Y Petrov, R Piegaia, T Pierog, P Pieroni, M Pimenta, V Pirronello, M Platino, M Plum, A Porcelli, C Porowski, P Privitera, M Prouza, V Purrello, EJ Quel, S Querchfeld, S Quinn, J Rautenberg, O Ravel, D Ravignani, B Revenu, J Ridky, S Riggi, M Risse, P Ristori, V Rizi, J Roberts, WR de Carvalho, IR Cabo, GR Fernandez, JR Rojo, MD Rodriguez-Frias, G Ros, J Rosado, T Rossler, M Roth, E Roulet, AC Rovero, C Ruehle, SJ Saffi, A Saftoiu, F Salamida, H Salazar, FS Greus, G Salina, F Sanchez, P Sanchez-Lucas, CE Santo, E Santos, EM Santos, F Sarazin, B Sarkar, R Sarmento, R Sato, N Scharf, V Scherini, H Schieler, P Schiffer, A Schmidt, O Scholten, H Schoorlemmer, P Schovanek, A Schulz, J Schulz, SJ Sciutto, A Segreto, M Settimo, A Shadkam, RC Shellard, I Sidelnik, G Sigl, O Sima, A Smialkowski, R Smida, GR Snow, P Sommers, J Sorokin, R Squartini, YN Srivastava, S Stanic, J Stapleton, J Stasielak, M Stephan, A Stutz, F Suarez, T Suomijaervi, AD Supanitsky, MS Sutherland, J Swain, Z Szadkowski, M Szuba, OA Taborda, A Tapia, M Tartare, NT Thao, VM Theodoro, J Tiffenberg, C Timmermans, CJT Peixoto, G Toma, L Tomankova, B Tome, A Tonachini, GT Elipe, DT Machado, P Travnicek, E Trovato, M Tueros, R Ulrich, M Unger, M Urban, JF Valdes Galicia, I Valino, L Valore, G van Aar, AM van den Berg, S van Velzen, A van Vliet, E Varela, BV Cardenas, G Varner, JR Vazquez, RA Vazquez, D Veberic, V Verzi, J Vicha, M Videla, L Villasenor, B Vlcek, S Vorobiov, H Wahlberg, O Wainberg, D Walz, AA Watson, M Weber, K Weidenhaupt, A Weindl, F Werner, BJ Whelan, A Widom, L Wiencke, B Wilczynska, H Wilczynski, M Will, C Williams, T Winchen, D Wittkowski, B Wundheiler, S Wykes, T Yamamoto, T Yapici, P Younk, G Yuan, A Yushkov, B Zamorano, E Zas, D Zavrtanik, M Zavrtanik, I Zaw, A Zepeda, J Zhou, Y Zhu, MZ Silva, M Ziolkowski, PA Collaborat

Multimessenger search for sources of gravitational waves and high-energy neutrinos: Initial results for LIGO-Virgo and IceCube

Physical Review D American Physical Society D90 (2014) 102002-102002

Aartsen, S Sarkar

We report the results of a multimessenger search for coincident signals from the LIGO and Virgo gravitational-wave observatories and the partially completed IceCube high-energy neutrino detector, including periods of joint operation between 2007-2010. These include parts of the 2005-2007 run and the 2009-2010 run for LIGO-Virgo, and IceCube's observation periods with 22, 59 and 79 strings. We find no significant coincident events, and use the search results to derive upper limits on the rate of joint sources for a range of source emission parameters. For the optimistic assumption of gravitational-wave emission energy of $10^{-2}$\,M$_\odot$c$^2$ at $\sim 150$\,Hz with $\sim 60$\,ms duration, and high-energy neutrino emission of $10^{51}$\,erg comparable to the isotropic gamma-ray energy of gamma-ray bursts, we limit the source rate below $1.6 \times 10^{-2}$\,Mpc$^{-3}$yr$^{-1}$. We also examine how combining information from gravitational waves and neutrinos will aid discovery in the advanced gravitational-wave detector era.

Searches for extended and point-like neutrino sources with four years of IceCube data

Astrophysical Journal IOP Publishing 796 (2014) 109-

Aartsen, S Sarkar

We present results on searches for point-like sources of neutrinos using four years of IceCube data, including the first year of data from the completed 86-string detector. The total livetime of the combined dataset is 1,373 days. For an E$^{-2}$ spectrum the median sensitivity at 90\% C.L. is $\sim 10^{-12}$ TeV$^{-1}$cm$^{-2}$s$^{-1}$ for energies between 1 TeV$-$1 PeV in the northern sky and $\sim 10^{-11}$ TeV$^{-1}$cm$^{-2}$s$^{-1}$ for energies between 100 TeV $-$ 100 PeV in the southern sky. The sensitivity has improved from both the additional year of data and the introduction of improved reconstructions compared to previous publications. In addition, we present the first results from an all-sky search for extended sources of neutrinos. We update results of searches for neutrino emission from stacked catalogs of sources, and test five new catalogs; two of Galactic supernova remnants and three of active galactic nuclei. In all cases, the data are compatible with the background-only hypothesis, and upper limits on the flux of muon neutrinos are reported for the sources considered.

Search for a diffuse flux of astrophysical muon neutrinos with the IceCube 59-string configuration

Physical Review D American Physical Society 89 (2014)

MG Aartsen, R Abbasi, M Ackermann, S Sarkar

A search for high-energy neutrinos was performed using data collected by the IceCube Neutrino Observatory from May 2009 to May 2010, when the array was running in its 59-string configuration. The data sample was optimized to contain muon neutrino induced events with a background contamination of atmospheric muons of less than 1%. These data, which are dominated by atmospheric neutrinos, are analyzed with a global likelihood fit to search for possible contributions of prompt atmospheric and astrophysical neutrinos, neither of which have yet been identified. Such signals are expected to follow a harder energy spectrum than conventional atmospheric neutrinos. In addition, the zenith angle distribution differs for astrophysical and atmospheric signals. A global fit of the reconstructed energies and directions of observed events is performed, including possible neutrino flux contributions for an astrophysical signal and atmospheric backgrounds as well as systematic uncertainties of the experiment and theoretical predictions. The best fit yields an astrophysical signal flux for νμ+ν̄μ of E2·Φ(E)=0.25×10-8GeVcm-2s-1sr-1, and a zero prompt component. Although the sensitivity of this analysis for astrophysical neutrinos surpasses the Waxman and Bahcall upper bound, the experimental limit at 90% confidence level is a factor of 1.5 above at a flux of E2·Φ(E)=1.44×10-8GeVcm-2s-1sr-1.

PINGU Sensitivity to the Neutrino Mass Hierarchy

Snowmass 2013 Division of Particles and Fields of the American Physical Society 2013 (2013)

MG Aartsen

<p style="text-align:justify;"> The neutrino mass hierarchy is one of the few remaining unknown parameters in the neutrino sector and hence a primary focus of the experimental community. The Precision IceCube Next Generation Upgrade (PINGU) experiment, to be co-located with the IceCube DeepCore detector in the deep Antarctic glacier, is being designed to provide a first definitive measurement of the mass hierarchy. We have conducted feasibility studies for the detector design that demonstrate a statistically-limited sensitivity to the hierarchy of 2.1σ to 3.4σ per year is possible, depending on the detector geometry (20 to 40 strings) and analysis efficiencies. First studies of the effects of systematic and theoretical uncertainties show limited impact on the overall sensitivity to the hierarchy. Assuming deployment of the first array elements in the 2016/17 austral summer season a 3σ measurement of the hierarchy is anticipated with PINGU in 2020. </p>

Measurement of the cosmic ray energy spectrum with IceTop-73

PHYSICAL REVIEW D 88 (2013) ARTN 042004

MG Aartsen, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, S Bechet, JB Tjus, K-H Becker, ML Benabderrahmane, S BenZvi, P Berghaus, D Berley, E Bernardini, A Bernhard, D Bertrand, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, S Bohaichuk, C Bohm, D Bose, S Boeser, O Botner, L Brayeur, H-P Bretz, AM Brown, R Bruijn, J Brunner, M Carson, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, F Clevermann, S Coenders, S Cohen, DF Cowen, AHC Silva, M Danninger, J Daughhetee, JC Davis, C De Clercq, S De Ridder, P Desiati, KD de Vries, M de With, T DeYoung, JC Diaz-Velez, M Dunkman, R Eagan, B Eberhardt, J Eisch, RW Ellsworth, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Gluesenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Gora, DT Grandmont, D Grant, A Gross, C Ha, AH Ismail, P Hallen, A Hallgren, F Halzen, K Hanson, D Heereman, D Heinen, K Helbing, R Hellauer, S Hickford, GC Hill, KD Hoffman, R Hoffmann, A Homeier, K Hoshina, W Huelsnitz, PO Hulth, K Hultqvist, S Hussain, A Ishihara, E Jacobi, J Jacobsen, K Jagielski, GS Japaridze, K Jero, O Jlelati, B Kaminsky, A Kappes, T Karg, A Karle, JL Kelley, J Kiryluk, J Klaes, SR Klein, J-H Koehne, G Kohnen, H Kolanoski, L Koepke, C Kopper, S Kopper, DJ Koskinen, M Kowalski, M Krasberg, K Krings, G Kroll, J Kunnen, N Kurahashi, T Kuwabara, M Labare, H Landsman, MJ Larson, M Lesiak-Bzdak, M Leuermann, J Leute, J Luenemann, O Maciias, J Madsen, G Maggi, R Maruyama, K Mase, HS Matis, F McNally, K Meagher, M Merck, T Meures, S Miarecki, E Middell, N Milke, J Miller, L Mohrmann, T Montaruli, R Morse, R Nahnhauer, U Naumann, H Niederhausen, SC Nowicki, DR Nygren, A Obertacke, S Odrowski, A Olivas, A Omairat, A O'Murchadha, L Paul, JA Pepper, CP de los Heros, C Pfendner, D Pieloth, E Pinat, J Posselt, PB Price, GT Przybylski, L Raedel, M Rameez, K Rawlins, P Redl, R Reimann, E Resconi, W Rhode, M Ribordy, M Richman, B Riedel, JP Rodrigues, C Rott, T Ruhe, B Ruzybayev, D Ryckbosch, SM Saba, T Salameh, H-G Sander, M Santander, S Sarkar, K Schatto, F Scheriau, T Schmidt, M Schmitz, S Schoenen, S Schoeneberg, A Schoenwald, A Schukraft, L Schulte, O Schulz, D Seckel, Y Sestayo, S Seunarine, R Shanidze, C Sheremata, MWE Smith, D Soldin, GM Spiczak, C Spiering, M Stamatikos, T Stanev, A Stasik, T Stezelberger, RG Stokstad, A Stoessl, EA Strahler, R Strom, GW Sullivan, H Taavola, I Taboada, A Tamburro, A Tepe, S Ter-Antonyan, G Tesic, S Tilav, PA Toale, S Toscano, E Unger, M Usner, S Vallecorsa, N van Eijndhoven, A Van Overloop, J van Santen, M Vehring, M Voge, M Vraeghe, C Walck, T Waldenmaier, M Wallraff, C Weaver, M Wellons, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, CH Wiebusch, DR Williams, H Wissing, M Wolf, TR Wood, K Woschnagg, C Xu, DL Xu, XW Xu, JP Yanez, G Yodh, S Yoshida, P Zarzhitsky, J Ziemann, S Zierke, M Zoll, I Collaboration

IceCube search for dark matter annihilation in nearby galaxies and galaxy clusters

Physical Review D - Particles, Fields, Gravitation and Cosmology 88 (2013)

MG Aartsen, R Abbasi, Y Abdou, M Ackermann, J Adams, JA Aguilar, M Ahlers, D Altmann, J Auffenberg, X Bai, M Baker, SW Barwick, V Baum, R Bay, JJ Beatty, S Bechet, J Becker Tjus, KH Becker, ML Benabderrahmane, S Benzvi, P Berghaus, D Berley, E Bernardini, A Bernhard, D Bertrand, DZ Besson, G Binder, D Bindig, M Bissok, E Blaufuss, J Blumenthal, DJ Boersma, S Bohaichuk, C Bohm, D Bose, S Böser, O Botner, L Brayeur, HP Bretz, AM Brown, R Bruijn, J Brunner, M Carson, J Casey, M Casier, D Chirkin, A Christov, B Christy, K Clark, F Clevermann, S Coenders, S Cohen, DF Cowen, AH Cruz Silva, M Danninger, J Daughhetee, JC Davis, M Day, C De Clercq, S De Ridder, P Desiati, KD De Vries, M De With, T Deyoung, JC Díaz-Vélez, M Dunkman, R Eagan, B Eberhardt, J Eisch, RW Ellsworth, S Euler, PA Evenson, O Fadiran, AR Fazely, A Fedynitch, J Feintzeig, T Feusels, K Filimonov, C Finley, T Fischer-Wasels, S Flis, A Franckowiak, K Frantzen, T Fuchs, TK Gaisser, J Gallagher, L Gerhardt, L Gladstone, T Glüsenkamp, A Goldschmidt, G Golup, JG Gonzalez, JA Goodman, D Góra, DT Grandmont, D Grant, A Groß, C Ha, A Haj Ismail, P Hallen

We present the results of a first search for self-annihilating dark matter in nearby galaxies and galaxy clusters using a sample of high-energy neutrinos acquired in 339.8 days of live time during 2009/10 with the IceCube neutrino observatory in its 59-string configuration. The targets of interest include the Virgo and Coma galaxy clusters, the Andromeda galaxy, and several dwarf galaxies. We obtain upper limits on the cross section as a function of the weakly interacting massive particle mass between 300 GeV and 100 TeV for the annihilation into bb̄, W+W-, τ+τ -, μ+μ-, and νν̄. A limit derived for the Virgo cluster, when assuming a large effect from subhalos, challenges the weakly interacting massive particle interpretation of a recently observed GeV positron excess in cosmic rays. © 2013 American Physical Society.

Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory

Journal of Cosmology and Astroparticle Physics 2013 (2013)

P Abreu, M Aglietta, M Ahlers, EJ Ahn, IFM Albuquerque, I Allekotte, J Allen, P Allison, A Almela, J Alvarez Castillo, J Alvarez-Mũniz, R Alves Batista, M Ambrosio, A Aminaei, L Anchordoqui, S Andringa, T Antǐci'c, C Aramo, F Arqueros, H Asorey, P Assis, J Aublin, M Ave, M Avenier, G Avila, AM Badescu, KB Barber, AF Barbosa, R Bardenet, B Baughmanc, J Bäuml, C Baus, JJ Beatty, KH Becker, A Belĺetoile, JA Bellido, S BenZvi, C Berat, X Bertou, PL Biermann, P Billoir, F Blanco, M Blanco, C Bleve, H Bl̈umer, M Bohã̌cov́a, D Boncioli, C Bonifazi, R Bonino, N Borodai, J Brack, I Brancus, P Brogueira, WC Brown, P Buchholz, A Bueno, L Buroker, RE Burton, M Buscemi, KS Caballero-Mora, B Caccianiga, L Caramete, R Caruso, A Castellina, G Cataldi, L Cazon, R Cester, J Chauvin, SH Cheng, A Chiavassa, JA Chinellato, J Chirinos Diaz, J Chudoba, M Cilmo, RW Clay, G Cocciolo, R Colalillo, L Collica, MR Coluccia, R Conceição, F Contreras, H Cook, MJ Cooper, J Coppens, S Coutu, CE Covault, A Criss, J Cronin, A Curutiu, R Dallier, B Daniel, S Dasso, K Daumiller, BR Dawson, RM De Almeida, M De Domenico, C De Donato, SJ De Jong, G De La Vega, WJM De Mello Junior

We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The density of uniformly distributed sources of equal intrinsic intensity was found to be larger than ∼ (0.06-5) × 10-4 Mpc-3 at 95% CL, depending on the magnitude of the magnetic deflections. Similar bounds, in the range (0.2-7) × 10-4 Mpc-3, were obtained for sources following the local matter distribution. © 2013 IOP Publishing Ltd and Sissa Medialab srl.

Introducing the CTA concept


BS Acharya, M Actis, T Aghajani, G Agnetta, J Aguilar, F Aharonian, M Ajello, A Akhperjanian, M Alcubierre, J Aleksic, R Alfaro, E Aliu, AJ Allafort, D Allan, I Allekotte, E Amato, J Anderson, EO Anguener, LA Antonelli, P Antoranz, A Aravantinos, T Arlen, T Armstrong, H Arnaldi, L Arrabito, K Asano, T Ashton, HG Asorey, Y Awane, H Baba, A Babic, N Baby, J Baehr, A Bais, C Baixeras, S Bajtlik, M Balbo, D Balis, C Balkowski, A Bamba, R Bandiera, A Barber, C Barbier, M Barcelo, A Barnacka, J Barnstedt, U Barres de Almeida, JA Barrio, A Basili, S Basso, D Bastieri, C Bauer, A Baushev, J Becerra, Y Becherini, KC Bechtol, JB Tjus, V Beckmann, W Bednarek, B Behera, M Belluso, W Benbow, J Berdugo, K Berger, F Bernard, T Bernardino, K Bernloehr, N Bhat, S Bhattacharyya, C Bigongiari, A Biland, S Billotta, T Bird, E Birsin, E Bissaldi, J Biteau, M Bitossi, S Blake, O Blanch Bigas, P Blasi, A Bobkov, V Boccone, M Boettcher, L Bogacz, J Bogart, M Bogdan, C Boisson, J Boix Gargallo, J Bolmont, G Bonanno, A Bonardi, T Bonev, P Bonifacio, G Bonnoli, P Bordas, A Borgland, J Borkowski, R Bose, O Botner, A Bottani, L Bouchet, M Bourgeat, C Boutonnet, A Bouvier, S Brau-Nogue, I Braun, T Bretz, M Briggs, T Bringmann, P Brook, P Brun, L Brunetti, T Buanes, J Buckley, R Buehler, V Bugaev, A Bulgarelli, T Bulik, G Busetto, S Buson, K Byrum, M Cailles, R Cameron, J Camprecios, R Canestrari, S Cantu, M Capalbi, P Caraveo, E Carmona, A Carosi, J Carr, P-H Carton, S Casanova, M Casiraghi, O Catalano, S Cavazzani, S Cazaux, M Cerruti, E Chabanne, P Chadwick, C Champion, A Chen, J Chiang, L Chiappetti, M Chikawa, VR Chitnis, F Chollet, J Chudoba, M Cieslar, A Cillis, J Cohen-Tanugi, S Colafrancesco, P Colin, J Calome, S Colonges, M Compin, P Conconi, V Conforti, V Connaughton, J Conrad, JL Contreras, P Coppi, P Corona, D Corti, J Cortina, L Cossio, H Costantini, G Cotter, B Courty, S Couturier, S Covino, G Crimi, SJ Criswell, J Croston, G Cusumano, M Dafonseca, O Dale, M Daniel, J Darling, I Davids, F Dazzi, A De Angelis, V De Caprio, F De Frondat, EM de Gouveia Dal Pino, I de la Calle, GA De La Vega, RDLR Lopez, B De Lotto, A De Luca, JRT de Mello Neto, M de Naurois, Y de Oliveira, E de Ona Wilhelmi, V de Souza, G Decerprit, G Decock, C Deil, E Delagnes, G Deleglise, C Delgado, D Della Volpe, P Demange, G Depaola, A Dettlaff, A Di Paola, F Di Pierro, C Diaz, J Dick, R Dickherber, H Dickinson, V Diez-Blanco, S Digel, D Dimitrov, G Disset, A Djannati-Atai, M Doert, M Dohmke, W Domainko, DD Prester, A Donat, D Dorner, M Doro, J-L Dournaux, G Drake, D Dravins, L Drury, F Dubois, R Dubois, G Dubus, C Dufour, D Dumas, J Dumm, D Durand, J Dyks, M Dyrda, J Ebr, E Edy, K Egberts, P Eger, S Einecke, C Eleftheriadis, S Elles, D Emmanoulopoulos, D Engelhaupt, R Enomoto, J-P Ernenwein, M Errando, A Etchegoyen, P Evans, A Falcone, D Fantinel, K Farakos, C Farnier, G Fasola, B Favill, E Fede, S Federici, S Fegan, F Feinstein, D Ferenc, P Ferrando, M Fesquet, A Fiasson, E Fillin-Martino, D Fink, C Finley, JP Finley, M Fiorini, R Firpo Curcoll, H Flores, D Florin, W Focke, C Foehr, E Fokitis, L Font, G Fontaine, M Fornasa, A Foerster, L Fortson, N Fouque, A Franckowiak, C Fransson, G Fraser, R Frei, IFM Albuquerque, L Fresnillo, C Fruck, Y Fujita, Y Fukazawa, Y Fukui, S Funk, W Gaebele, S Gabici, R Gabriele, A Gadola, N Galante, D Gall, Y Gallant, J Gamez-Garcia, B Garcia, R Garcia Lopez, D Gardiol, D Garrido, L Garrido, D Gascon, M Gaug, J Gaweda, L Gebremedhin, N Geffroy, L Gerard, A Ghedina, M Ghigo, E Giannakaki, F Gianotti, S Giarrusso, G Giavitto, B Giebels, V Gika, P Giommi, N Girard, E Giro, A Giuliani, T Glanzman, J-F Glicenstein, N Godinovic, V Golev, M Gomez Berisso, J Gomez-Ortega, MM Gonzalez, A Gonzalez, F Gonzalez, A Gonzalez Munoz, KS Gothe, M Gougerot, R Graciani, P Grandi, F Granena, J Granot, G Grasseau, R Gredig, A Green, T Greenshaw, T Gregoire, O Grimm, J Grube, M Grudzinska, V Gruev, S Gruenewald, J Grygorczuk, V Guarino, S Gunji, G Gyuk, D Hadasch, R Hagiwara, J Hahn, N Hakansson, A Hallgren, N Hamer Heras, S Hara, MJ Hardcastle, J Harris, T Hassan, K Hatanaka, T Haubold, A Haupt, T Hayakawa, M Hayashida, R Heller, F Henault, G Henri, G Hermann, R Hermel, A Herrero, N Hidaka, J Hinton, D Hoffmann, W Hofmann, P Hofverberg, J Holder, D Horns, D Horville, J Houles, M Hrabovsky, D Hrupec, H Huan, B Huber, J-M Huet, G Hughes, TB Humensky, J Huovelin, A Ibarra, JM Illa, D Impiombato, S Incorvaia, S Inoue, Y Inoue, K Ioka, E Ismailova, C Jablonski, A Jacholkowska, M Jamrozy, M Janiak, P Jean, C Jeanney, JJ Jimenez, T Jogler, T Johnson, L Journet, C Juffroy, I Jung, P Kaaret, S Kabuki, M Kagaya, J Kakuwa, C Kalkuhl, R Kankanyan, A Karastergiou, K Kaercher, M Karczewski, S Karkar, A Kasperek, D Kastana, H Katagiri, J Kataoka, K Katarzynski, U Katz, N Kawanaka, B Kellner-Leidel, H Kelly, E Kendziorra, B Khelifi, DB Kieda, T Kifune, T Kihm, T Kishimoto, K Kitamoto, W Kluzniak, C Knapic, JW Knapp, J Knoedlseder, F Koeck, J Kocot, K Kodani, J-H Koehne, K Kohri, K Kokkotas, D Kolitzus, N Komin, I Kominis, Y Konno, H Koeppel, P Korohoda, K Kosack, G Koss, R Kossakowski, P Kostka, R Koul, G Kowal, S Koyama, J Koziol, T Kraehenbuehl, J Krause, H Krawzcynski, F Krennrich, A Krepps, A Kretzschmann, R Krobot, P Krueger, H Kubo, VA Kudryavtsev, J Kushida, A Kuznetsov, A La Barbera, N La Palombara, V La Parola, G La Rosa, K Lacombe, G Lamanna, J Lande, D Languignon, J Lapington, P Laporte, C Lavalley, T Le Flour, A Le Padellec, S-H Lee, WH Lee, MA Leigui de Oliveira, D Lelas, J-P Lenain, DJ Leopold, T Lerch, L Lessio, B Lieunard, E Lindfors, A Liolios, A Lipniacka, H Lockart, T Lohse, S Lombardi, A Lopatin, M Lopez, R Lopez-Coto, A Lopez-Oramas, A Lorca, E Lorenz, P Lubinski, F Lucarelli, H Luedecke, J Ludwin, PL Luque-Escamilla, W Lustermann, O Luz, E Lyard, MC Maccarone, TJ Maccarone, GM Madejski, A Madhavan, M Mahabir, G Maier, P Majumdar, G Malaguti, S Maltezos, A Manalaysay, A Mancilla, D Mandat, G Maneva, A Mangano, P Manigot, K Mannheim, I Manthos, N Maragos, A Marcowith, M Mariotti, M Marisaldi, S Markoff, A Marszalek, C Martens, J Marti, J-M Martin, P Martin, G Martinez, F Martinez, M Martinez, A Masserot, A Mastichiadis, A Mathieu, H Matsumoto, F Mattana, S Mattiazzo, G Maurin, S Maxfield, J Maya, D Mazin, L Mc Comb, N McCubbin, I McHardy, R McKay, C Medina, C Melioli, D Melkumyan, S Mereghetti, P Mertsch, M Meucci, J Michalowski, P Micolon, A Mihailidis, T Mineo, M Minuti, N Mirabal, F Mirabel, JM Miranda, R Mirzoyan, T Mizuno, B Moal, R Moderski, I Mognet, E Molinari, M Molinaro, T Montaruli, I Monteiro, P Moore, A Moralejo Olaizola, M Mordalska, C Morello, K Mori, F Mottez, Y Moudden, E Moulin, I Mrusek, R Mukherjee, P Munar-Adrover, H Muraishi, K Murase, A Murphy, S Nagataki, T Naito, D Nakajima, T Nakamori, K Nakayama, C Naumann, D Naumann, M Naumann-Godo, P Nayman, D Nedbal, D Neise, L Nellen, V Neustroev, N Neyroud, L Nicastro, J Nicolau-Kuklinski, A Niedzwiecki, J Niemiec, D Nieto, A Nikolaidis, K Nishijima, S Nolan, R Northrop, D Nosek, N Nowak, A Nozato, P O'Brien, Y Ohira, M Ohishi, S Ohm, H Ohoka, T Okuda, A Okumura, J-F Olive, RA Ong, R Orito, M Orr, J Osborne, M Ostrowski, LA Otero, N Otte, E Ovcharov, I Oya, A Ozieblo, L Padilla, S Paiano, D Paillot, A Paizis, S Palanque, M Palatka, J Pallota, K Panagiotidis, J-L Panazol, D Paneque, M Panter, R Paoletti, A Papayannis, G Papyan, JM Paredes, G Pareschi, G Parks, J-M Parraud, D Parsons, MP Arribas, M Pech, G Pedaletti, V Pelassa, D Pelat, MDC Perez, M Persic, P-O Petrucci, B Peyaud, A Pichel, S Pita, F Pizzolato, L Platos, R Platzer, L Pogosyan, M Pohl, G Pojmanski, JD Ponz, W Potter, J Poutanen, E Prandini, J Prast, R Preece, F Profeti, H Prokoph, M Prouza, M Proyetti, I Puerto-Gimenez, G Puehlhofer, I Puljak, M Punch, R Pyziol, EJ Quel, J Quinn, A Quirrenbach, E Racero, PJ Rajda, P Ramon, R Rando, RC Rannot, M Rataj, M Raue, P Reardon, O Reimann, A Reimer, O Reimer, K Reitberger, M Renaud, S Renner, B Reville, W Rhode, M Ribo, M Ribordy, MG Richer, J Rico, J Ridky, F Rieger, P Ringegni, J Ripken, PR Ristori, A Riviere, S Rivoire, L Rob, U Roeser, R Rohlfs, G Rojas, P Romano, W Romaszkan, GE Romero, S Rosen, SR Lees, D Ross, G Rouaix, J Rousselle, S Rousselle, AC Rovero, F Roy, S Royer, B Rudak, C Rulten, M Rupinski, F Russo, F Ryde, B Sacco, EO Saemann, A Saggion, V Safiakian, K Saito, T Saito, Y Saito, N Sakaki, R Sakonaka, A Salini, F Sanchez, M Sanchez-Conde, A Sandoval, H Sandaker, E Sant'Ambrogio, A Santangelo, EM Santos, A Sanuy, L Sapozhnikov, S Sarkar, N Sartore, H Sasaki, K Satalecka, M Sawada, V Scalzotto, V Scapin, M Scarcioffolo, J Schafer, T Schanz, S Schlenstedt, R Schlickeiser, T Schmidt, J Schmoll, P Schovanek, M Schroedter, C Schultz, J Schultze, A Schulz, K Schure, T Schwab, U Schwanke, J Schwarz, S Schwarzburg, T Schweizer, S Schwemmer, A Segreto, J-H Seiradakis, GH Sembroski, K Seweryn, M Sharma, M Shayduk, RC Shellard, J Shi, T Shibata, A Shibuya, E Shum, L Sidoli, M Sidz, J Sieiro, M Sikora, J Silk, A Sillanpaa, BB Singh, J Sitarek, C Skole, R Smareglia, A Smith, D Smith, J Smith, N Smith, D Sobczynska, H Sol, G Sottile, M Sowinski, F Spanier, D Spiga, S Spyrou, V Stamatescu, A Stamerra, R Starling, L Stawarz, R Steenkamp, C Stegmann, S Steiner, N Stergioulas, R Sternberger, M Sterzel, F Stinzing, M Stodulski, U Straumann, E Strazzeri, L Stringhetti, A Suarez, M Suchenek, R Sugawara, K-H Sulanke, S Sun, AD Supanitsky, T Suric, P Sutcliffe, J Sykes, M Szanecki, T Szepieniec, A Szostek, G Tagliaferri, H Tajima, H Takahashi, K Takahashi, L Takalo, H Takami, C Talbot, J Tammi, M Tanaka, S Tanaka, J Tasan, M Tavani, J-P Tavernet, LA Tejedor, I Telezhinsky, P Temnikov, C Tenzer, Y Terada, R Terrier, M Teshima, V Testa, D Tezier, D Thuermann, L Tibaldo, O Tibolla, A Tiengo, M Tluczykont, CJ Todero Peixoto, F Tokanai, M Tokarz, K Toma, K Torii, M Tornikoski, DF Torres, M Torres, G Tosti, T Totani, C Toussenel, G Tovmassian, P Travnicek, M Trifoglio, I Troyano, K Tsinganos, H Ueno, K Umehara, SS Upadhya, T Usher, M Uslenghi, JF Valdes-Galicia, P Vallania, G Vallejo, W van Driel, C van Eldik, J Vandenbrouke, J Vanderwalt, H Vankov, G Vasileiadis, V Vassiliev, D Veberic, I Vegas, S Vercellone, S Vergani, C Veyssiere, JP Vialle, A Viana, M Videla, P Vincent, S Vincent, J Vink, N Vlahakis, L Vlahos, P Vogler, A Vollhardt, H-P von Gunten, S Vorobiov, C Vuerli, V Waegebaert, R Wagner, RG Wagner, S Wagner, SP Wakely, R Walter, T Walther, K Warda, R Warwick, P Wawer, R Wawrzaszek, N Webb, P Wegner, A Weinstein, Q Weitzel, R Welsing, M Werner, H Wetteskind, R White, A Wierzcholska, S Wiesand, M Wilkinson, DA Williams, R Willingale, K Winiarski, R Wischnewski, L Wisniewski, M Wood, A Woernlein, Q Xiong, KK Yadav, H Yamamoto, T Yamamoto, R Yamazaki, S Yanagita, JM Yebras, D Yelos, A Yoshida, T Yoshida, T Yoshikoshi, V Zabalza, M Zacharias, A Zajczyk, R Zanin, A Zdziarski, A Zech, A Zhao, X Zhou, K Zietara, J Ziolkowski, P Ziolkowski, V Zitelli, C Zurbach, P Zychowski, CTA Consortium

A New Era in Gamma-Ray Astronomy with the Cherenkov Telescope Array


J Hinton, S Sarkar, D Torres, J Knapp